1. Field of the Invention
The present invention relates to a high temperature superconducting coil where an oxide superconducting wire is wound in a coil and also relates to a method of manufacturing thereof.
2. Description of the Background Art
A high temperature superconductive material known as a ceramics based superconductor is under study to be used as a thin tape type wire by applying plastic working to a high temperature superconductor while being metal-coated. The combination of such plastic working and thermal treatment can result in obtaining a tape type oxide superconducting wire having high critical density. The application of such a tape type oxide superconducting wire is now being considered to bus bar conductors, cable conductors, coils, etc.
However, such an oxide superconducting wire had a characteristic problem of low resistance to mechanical strain. Therefore, a coil formed of an oxide superconducting wire had a problem of degraded performance caused by thermal strain during a thermal heat cycle and mechanical strain by the electromagnetic force of the coil itself.